1. Technical Field
The present invention relates to a vehicle lock device. More specifically, the invention relates to a lock device for transmitting an unlocking force from a lock cylinder in a lock cylinder casing to an operating arm in a locking mechanism.
2. Background Information
Transmitting the unlocking or locking force between a lock cylinder and a locking mechanism by means of rods or draw or push cables fixed to an operating arm in the locking mechanism is known. One example of such a known device is disclosed in European Patent No. 0 475 037. However, such known devices can be relatively easy for a car thief to tamper with. For example, where a draw cable is used, the car thief can slip a hooked implement down inside a vehicle door for catching hold of the cable and pulling it in order to unlock the door. In order to make this more difficult, it is now common to arrange protective covers in the vehicle door that prevent access to the cable. Still, the covers increase the weight and cost of the vehicle.
Where rods are used to transmit the unlocking or locking force, a car thief can sometimes manage to displace the rod enough to unlock the door. This is accomplished by introducing an implement into the lock cylinder and breaking the lock cylinder and the lock cylinder casing around its fixing in the vehicle. In order to make this more difficult, it is common to provide the fixing for the lock cylinder casing with strong reinforcements so that the necessary bending moment cannot be easily applied to the lock cylinder casing. However, as before, these reinforcements also increase the weight and cost of the vehicle. Furthermore, both of the above-mentioned solutions may be adversely affected in the event of a collision at moderate speed, since deformation of the vehicle adjacent to the locking devices may mean that the locking function/unlocking function is jeopardized by the exposure of a cable to tensile force or by displacement of a rod.
Accordingly, there is a need for a locking device that is simple in design, low in cost and weight, while also difficult for a car thief to tamper with.
The present invention provides a device for transmitting an unlocking force from a lock cylinder arranged in a lock cylinder casing to a locking mechanism. The invention is especially applicable to vehicle locks. The device is simple, has a low weight and entails a relatively low cost. At the same time, the device is very difficult for a car thief to tamper with in order to unlock the door.
The present invention further provides a device for transmitting an unlocking force from a lock cylinder to a locking mechanism that remains substantially unaffected and safeguards the opening function in the event of a collision at moderate speed.
According to one embodiment of the present invention a device for transmitting an unlocking force from a lock cylinder arranged in a lock cylinder casing to a locking mechanism or operating arm includes a cable sheath. The cable sheath has a first end that is fixed or connected to the lock cylinder casing, and a second end fixed or connected to the operating arm of the locking mechanism. A cable is arranged in the cable sheath and is operatively connected to the lock cylinder with a first end of the cable. The first cable end is designed, when acted upon by the lock cylinder for unlocking the door, to be pushed into the cable sheath, causing a second cable free end to be pushed out the other end of the cable sheath and brought into engagement with the operating arm. With the operating arm, the second cable end is able to transmit to the locking mechanism the requisite force or movement needed to bring the locking mechanism from a locked position to an unlocked position.
A displacement element for the cable is arranged in the lock cylinder. The element forms a moment arm between the axis of rotation of the lock cylinder and the placement of the first cable end in the displacement element. The element is designed to impart to the first cable end the necessary displacement in relation to the cable sheath when acted upon by the lock cylinder for unlocking the door. Additionally, the element receives and protects that part of the first cable end that protrudes from the first end of the cable sheath.
In one embodiment, the displacement element for the cable has a groove corresponding to the cable. The groove is of sufficient depth and length to accommodate the part of the cable that protrudes from the first end of the cable sheath.
In another embodiment of the invention, the operating arm, when not acted upon by the second free end of the cable, is designed to return to the locked position by device such as a spring.
The device according to the invention has a number of advantages. Among other things it is very difficult for a car thief to tamper with. The car thief cannot manage to unlock a vehicle door by slipping a hooked implement down inside the door, catching hold of the cable and pulling the latter. The protective covers now common in the vehicle doors can thereby be dispensed with, making it possible to reduce the weight and cost of the vehicle. Nor can the car thief, as may happen where rods are used for the transmission of forces, manage to displace the cables in relation to the cable sheath in order to unlock the door, by inserting an implement into the cylinder lock and breaking the cylinder lock and the lock cylinder casing around its fixing in the vehicle. This means that the reinforcements now common for fixing the lock cylinder casing can be dispensed with, which in turn means that it is possible to reduce the weight and cost of the vehicle. Furthermore, the solution according to the invention is not affected in the context of a collision at moderate speed, since certain deformation of the vehicle adjacent to the lock devices does not result in relative displacement between the cable and the cable sheath, thereby safeguarding the opening function following a collision at moderate speed.